Device for producing a room-closing air curtain



E. STEINER` 2,863,373

2 Sheets--Sheet 1 DEVICE FOR PRODUCING A ROOM-CLO SING AIR CURTAIN W 7 %V//M//V/M 4 E 4 Dec. 9, 1958 Filed Oct. 29, 1954 E. STEINER DEVICE FOR PRODUCING A ROOM-CLOSING AIR CURTAIN Filed Oct. 29, 1954 Dec. 9, 1958 2 Sheets-Sheet 2 ERNST STE/Nfl? ar KLM ATTORNEK United States Patent i DEVICE FOR PRODUCIN G A ROOM-CLOSING AIR CURTAIN Ernst Steiner, Zurich, Switzerland, assignor to Sifrag Spezialapparatebau & Ingenietrhureau it rei A. G., Bern, Switzerland Application October 29, 1954, Serial No. 465 680 12 Claims. (Cl. 98--36} of the invention these means comprises an adjustable t air distributor. A difierential pressure gauge is preferably provided, which measures the difference of the pressures in the rooms separated from each other by the air-curtain and which is arranged to act as a Supplementary controlling means for the fan producing the aircurtain.

The invention will now be described in more details and by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a diagrammatic vertical sectional view of a device for produc'ng a roonclosing air-curtain; the room to be closed from the outer atmosphere by means of the air-curtain is supposed to be located on the right side in this representation, p

Of Figs. 2 to 6 representing a preferred embodiment of the adjustable distributor, Fig. 2 is a sectional view in a vertical plane parallel to the main plane of the entry or exit to be closed by the curtain,

Fig. 3 is a sectional view taken along line-III-III of Fg. 2, a

Fig. 4 shows a detal of Fig. 2 on an enlarged scale,

Fig. 5 is a view similar to Fig. 4, the movable member being, however, shown in another position,

Fig. 6 is a perspective view of some members of the distributor, and

Fig. 7 is a sectional view through one of the members of the distributor.

In the Construction represented in Fig. 1, a floor 1 has a set-in grid 2 covering an air inlet chamber 3 located beneath an entry or exit. Above the latter is located an air outlet chamber 4 having an outlet opening 5 in which there is arranged an adjustable distributor 6 for an air-curtain 7. The distributor 6 is operatively connected by means of a servo-motor 8 to a control mechanism 9 which in turn is connected to a pressure gauge 10. The flow of air forming the air-curtain is produced by a fan 11 which draws the air from the inlet chamber 3 and delivers it to the outlet chamber 4 through a pipe 12. The air thus fiows in a closed circuit comprising the air-curtain. A heater 14 controlled by a device 13 is arranged between sections of the pipe 12. The reference numerals 15 and 16 designate two feelers of a difierential pressure gauge 17 controlling a servo-motor 13 which regulates an electric motor 19 driving the fan 11. i i

During operation, the motor 19 drives the fan 11 ice which then draws the air from the inlet chamber 3 through a strainer 21. The air delivered by the fan is heated at 14 before it reaches the outlet chamber 4; indeed a curtain of warm air is preterable to one formed by cold air.

The distributor 6 arranged in the opening 5 compels the air to flow in the direction of the arrow's 20. The flow of air forms a curtain in the entry or exit which has substantial depth in the direction of traflic through the said entry or exit, being deeper in that direction than is the average person, and that curtain is then again drawn into the chamber 3 through the grid 2. Particles of dust and the like entering this chamber together with the air drop onto the bottom of the chamber, from where they are removed by a spray of water. As shown in Fig.1, the curtain is outwardly inclined from top to bottom. The gauge 17 is sensible to any difference between the pressures existing in the spaces separated by the curtain and responds to such difference by so controlling the driving motor 19 of the fan 11 by means of the servo motor 18, that it rotates faster and increases the velocity of the air forming the curtain to stabilise the location of the latter. i i

This regulation is, however, only active in a limited range. As a Supplement to this first control means a second control means is used: the pressure gauge 10 is arranged at a place which is so chosen that during normal operation the air flow passes in front of it, but strikes it each time when the curtain is defiected inwardly by an outer perturbation acconpanied by a sudden increase of the outer pressure. Each time when the gauge 10 is struck by the deflected air flow, the ,control mechanism 9 acts onto the servo-motor 8 which then regulates the distributor 6 so that the direction of the air flow is tilted outwardly.

Other combinations are possible. The pressure gauge 10 might be arrarged to control the driving motor 19 of the fan, and the difierential pressure gauge 17 might be arranged to control thedistrbutor 6.. Another alternative would consst in providing an arrangement with two pressure gauges combined with electric control means so designed that the air-curtain is always located between the said two pressure gauges.

Tests have shown that the adjustable distributor should preferably be constructed as an assernbly of individual pivotable guide members 23 (Fgs. 3 to 6), which take up the whole width of the air-curtain. In the embodiment represented the guide members are metallic hollow bodies the cross section of which is an isosceles triangle standing on its base. The angle at the vertex is about 20 degrees. All guide members are pivotally mounted onboth ends in an angle iron 24. At the top each guide member has a projection 25 at least on one side. These projections are connected with one another by a rod 26, so that they may be pivoted in common. When the guide members assume the positon shown in Fig. 4, the air curtain is vertical. When the guide members 23 are displaced by the control mechanism by means of the ro d 26, as shown in Fig. 5, the air curtain, seen from the room to be closed thereby; is displaced outwards. triangular cross-section, the outlet opening is considerably diminished, so that, at a constant rotary speed of the fan, the air velocity in the curtain is increased, owing to which the curtain becomes more stable.

Since the ratio of pressure and speed is not the same at all points of the outlet chamber, the air fiowing downwards tends to ow sidewards, so that it may be that the exit or entry is not closed completely.

This drawback may be removed by providing corresponding guide plates above or below the adjustable con- Since the guide members are of trol m echanism 'Thereby, however, the height required for the exit chamber is enlarged, which is usually undesirable or not possible at all.

In the embodiment shown each guide member is pro- ,vided.wth severalguicle ,plates 27 p erpendicularto' the .faxi of rotation of this member. These plates have trapezoi dal; shape, so that they perrnitv a limited tlting "vihiid %3 1 1 33 as, s c l y ,show "5. rhy caus the air' curtain to uniformly close the ,wholewidthofthe room' opening s o that no "curtainless corners canfo rm Their height is greater than 'half the heightofthe guide members 23. Their numfbran'd fthir distanc effrom oneanother depend on the jihight and thesizeof theroom opening to be closed by theair curtainfi What 'Iclaim is:

` 1.'jA *device thatcan ,direct air across an opening ;to orrn an air "screen of substantial !depth for filling a ?substantial portion of said' .opening and that comprises "anair'inlet chamber; at `one ;side of said opening, an air 'outlet chamber at the opposite side of ,said opening,an *airpassagej'extending from said air inlet chamber to said 'air outlet cha `jrber,` an air-moving element to draw air into said air'inlet chamberand to move said air through {said "air passage to said air outlet chamber and across said opening to said air inlet chamber, a`motor that 'drives said' air-moving element to cause said air to enter said air inlet chamberand to pass through said air passage to said air ,outlet chamber and to move across said opening to 'said air `inlet chamber, a plurality of `closely adjacent, elongated elements that are spaced apart "depthwise of said opening in the direction of traffic throughfsaid opening and that are adjacent the exit of said air-outlet chamber, means rnovably mounting said elongated elements said chamber exit, a mechanism `for moving said elongated elements and thereby directing theair issuing from said air outlet chamber toward said air inlet chamber or outwardly of said opening, and -a control device that varies the velocity of the said air issuing from said air outlet chamber and passing between said'elongated elements, said control device 'normally maintaining the velocity of the said air issuing from said air outlet chamber at low value and said mechanism 'normally positioning said elongated elements for directing 'the said air issuing from said air outlet chamber toward said air inlet chamber, said control device increas- :ing the velocity of the said air issuing from said air outlet chamber and said mechanism positioning said elon- *gated elements for: directng the said air issuing from said airoutlet chamber outwardlyof said opening whenever a Wind capable of defiecting said air screen impinges upon said air screen.

2. A device that `can direct air across an opening to form an 'air screen of substantial depth for filling a substantial-portion.ofsaidopening and that comprises an air inlet'chamber at one side of said opening, an air out- `let chamber' at the .opposite side of said opening, an air passage extending from said arfinlet chamber' to said air outletchamber, an-air-movng element to draw air into said air inlet chamber and to move said air through said air passage .to said air outlet chamber and across said openingto s'aidair inlet chamber, a motor that drives said air-moving element to cause said air to enter said air inlet chamber, and to pass through said air passage to said air outlet-chamber 'and to move across said opening to said air inlet chamber, a plurality of closely adjacent, elongated elements that are spaced apart depthwise of said opening in the direction of traffic through said openingand that' are adjacent the exit of said air outlet chamber, means movably mounting said elongated elements iri-said chamber exit, amechanism for moving said elongated elements and thereby directng the air issuing from i ai Qutlet chamber toward said air inlet chamber or outwardly of said opening, and a control device that varies the velocity of the said air issuing from said air outlet chamber and passing between 'said elongated elements, said control device normally mantaining the yelocty of the said air issuing from said air outlet chamber at low value and said mechanism normally positioning said elongated elements for directng the said air issuing from said air outlet chamber toward said air inlet chamber, said control device increasing the velocity of the said air issuing from said air outlet chamber andsaid mechansm positioning said elongated elements for directing the said air issuing from said air outlet chamber outwardly ot said opening 'whenever a wind capable of defiectirg said air screen impinges upon said air screen, said control device being responsive to the difierences between the pressures exteriorly and nteriorlyof sad air screen, said elongated elements responding to said mechanism to move and define air-guiding passages inclined outwardly of said opening.

3. A device that can direct air across an opening to form an air screen of substantial depth for fillinga substantial portion of said ;openingand that comprses an ar inlet chamber at one side of said opening, an air outlet ,chamber `at the opposite side of said opening, an air 'passage extending from said air inlet chamber to said ar `outlet chamber, an air-movingelement to'draw ar nto said air inlet chamber and to move said air through said air passage to said air outlet chamber and across said opening tosaid air inletjchamber, a motor that drives said air-mov- `ments that are spaced apart depthwse of said opening in the direction of traffic through said opening and that are adjacent the exit of said air outlet chamber, means mov= ably mountng said elongated elements in said chamber exit, a mechanism for moving saidt elongatd elements and .thereby directng the air issuing from said air outlet chamber towrd said air inlet chamber or outwardly of said opening, and a control device-that varies the velocity of the said air issuing from said air outlet chamber and passing between said elongated elenents,said control device normally maintaining the velocity of the said ar issuing from said air outlet chamber at low value ,and said mechanism normally positioning said elongated elements for directng the said air issuing from said air outlet chamber toward said air inlet chamber, said control device increasing the velocity of the said air issuing :from said air outlet chamber and said mechanism positioning said elongated elements for directng the said air issuing from saidair outlet chamberoutwardly of saidopen ing whenever a wind capable oi defleting said air` screen irnpings upon said air screen, said controldevie being responsive toirinward deections ,ofvsaid ,air s creen, s aid elongated elements responding to said mechanisrn to of said opening; v

4. A device that' candirect air across .anopeningto form an air screen ofsu'ostrtial, depth for filling a-.pbstantial portion offsaid opening and that comprises-an ir inlet chamber atone sidetof saidopening, anair outlet chamber at the opposite side ofsaid opening, anair passage extending fromsaid `air inlet chamber to said air outlet chamber, an air-moving element .to draw airvint o said air inlet chamber and, .to move said air through said air passage to said air outlet chamber and across said opening to said air inlet chamber, said air outlet chamber having an exit that is ,adjacent said openingand that movie? and define i -endin Pas a e? i r lpu ws d i 'extends depthwise of saidopenirg' in the direction of traffic through said 'opening to provide an air screenttof substantial depth in the direction of traffic through said opening, a motor 'that drives said air-moving element to cause said ai to enter said air inlet chamber and topass through said air passage to said air outlet chamberand to move across said opening to said air inlet chamber, and a control device that varies the velocity of said 'air issuing from said air outlet chamber, said control device providing low velocity for the said air issuing from said air outlet chamber whenever there is no external wind impinging upon said air screen and providing higher velocity for the said air issuing from said air outlet chamber and thereby stablizing said air screen whenever a wind capable of deflectng said air screen impinges upon said air screen.

5. A device that can direct air across an opening to form an air screen of substantial depth for filling a substantial portion of said opening and that coinprises an air inlet chamber at one side of said opening, an air outlet chamber at the opposite side of said opening, an air passage extending from said air inlet chamber to said air outlet chamber, an ar-moving element to draw air into said air inlet chamberand to move said air through said air passage to said air outlet chamber and across said opening to said air inlet chamber, said air outlet chamber having an exit that is adjacent said opening and that extends depthwise of said opening in the direction of traffic through said opening to provide an air screen of substantial depth in the direction of traffic through said opening and being deeper than is the average person, a motor that drives said air-moving element to cause said air to enter said air inlet chamber and to pass through said air passage to said air outlet chamber and to move across said opening to said air inlet chamber, and a control device that varies the Velocity of said air issuing from said air outlet chamber, said control device providing low Velocity for the said air issuing from said air outlet chamber whenever there is no external wind irnpinging upon said air screen and providing higher velocity for the said air issuing from said air outlet chamber and thereby stabilizing said air screen whenever a wind capable of deflecting said air screen impinges upon said air screen, said control device being responsive to the differences between the pressures exteriorly and interiorly of said air screen to increase and decrease the velocity of the said air issuing from said air outlet chamber.

6. A device that` can direct air across an opening to form an air screen of substantial depth for filling a substantial portion of said opening and that comprises an air inlet chamber at one side of said opening, an air outlet chamber at the opposite side of said opening, an air passage extending from said air inlet' chamber to said air outlet chamber, an air-moving element to draw air into said air inlet chamber and to move said air through said air passage to said air outlet chamber and' across said opening to said air inlet chamber, said air outlet chamber having an exit that is adjacent said opening and that extends depthwise of said opening in the direction of trafiic through said opening to provide an air screen of substantial depth in the direction of traic through said opening, a motor that drives said air-moving element to cause said air to enter said air inlet chamber 'and to pass through said air passage to said air outlet chamber and to move across said opening to said air inlet chamber, and a control device that Varies the velocity of said air issuing from said air outlet chamber, said control device providing low Velocity for the said air issuing` from said air outlet chamber whenever there is no external wind impinging upon said air screen and providing higher velocity for the said air issuing from said air outlet chamber and thereby stablizing said 'air screen whenever a wind capable of defiecting said air screen impinges upon said air screen, said control device being responsive to inward defiections of said air screen to increase the velocity of the said air issuing from said air outlet chamber.

7. A device that can direct air across an opening to form an air screen of substantial depth for filling a substantial portion of said opening and that comprises an air inlet chamber at one side of said opening, an air outlet chamber at the opposite side of said opening, an air passage extending from said air inlet chamber to said air outlet chamber, an air-moving element to draw air` said opening in the direction of trafiic through said opening and that are adjacent the exit of said air outlet chamber to provide a plurality of air streams'of suficient velocity to extend across said opening, means movably mounting said elongated elements in said chamber exit,

and a mechanism for moving said elongated elements and` thereby directing the air issuing from said air outlet chamber and passing between said elongated elements toward said air inlet chamber or outwardly of said opening, said mechanisrn normally positioning said elongated elements for directing the said air issuing from said air outlet chamber toward said air inlet chamber, said mechanism positioning said elongated elements for directing the said air issuing from said air outlet chamber outwardly of said opening whenever a wind capable of deecting said air screen inpinges upon said air screen.

8. A device that can direct air across an opening to form an air screen of substantial depth for filling a substantial portion of said opening and that comprises an air inlet 'chamber at one side of said opening, an air outlet chamber at the opposite side of said opening, an air passage extending from said air inlet chamber to said air outlet chamber, an air-moving element to draw air into said air inlet chamber and to move said air through said air passage to said air outlet chamber and across said opening to said air inlet chamber, a motor that drives said air-moving element to cause said air to enter said air inlet chamber and to pass through said air passage to said air outlet chamber and to move across said opening to said air inlet chamber, a plurality of closely adjacent, elongated elements that are spaced apart depthwise of said opening in the direction of traffic through said opening and that are adjacent the exit of said air outlet chamber to provide a plurality of air streams of suficient velocity to extend across said opening, means movably mounting said elongated elements in said chamber exit, and a mechanism for moving said elongated elements and thereby directing the air issuing from said air outlet chamber and passing between said elongated elements toward said air inlet chamber or outwardly of said opening, said mechanism normally positioning said elongated elements for directing the said air issuing from said air outlet chamber toward said air inlet chamber, said mech-` anism positioning said elongated elements for directing the said air issuing from said air outlet chamberoutwardly of said opening whenever wind capable 'of defiecting said air screen impinges upon saidair screen, said mechanism being responsive to the differences between the pressures exteriorly and interiorly of said air screen to move said elongated elements and thereby provide air passages between said elongated elements that incline outwardly of said opening. l

9. A device that can direct air across an opening to form an air screen of substantial depth for filling a substantial portion of said opening and that comprises an air inlet chamber at one side of said opening, an air outlet chamber at the opposite side of said opening, an air passage extending from said air inlet chamber to said air outlet chamber, an air-moving element to draw air into said air inlet chamber and to move said air through said air passage to said air outlet chamber and across said opening to said air inlet chamber. a motor that drives said air-moving element to cause said air to enter said air inlet chamber and to pass through said air passage to said air outlet chamber and to move across said opening to said air inlet chamber, a plurality of closely adjacent,

&863378 o atdelem ts ha a e ,sp c an ,d pthwise ,o d lopeni n thedi m t a fi t rou h ,said pen- .g ga d ha a adia e he ex i a e outlet chamr,to provide a` plurality of air streams of sufficient veloitvto extend ;across said opening, means movably monntng said. elongatedelernents .in said charnbe' exit andarnejchanism formoving saidelongated elements and `'thereby directing the air issuing from said air outlet cham- ;her and passingbetweensaid elongated elements toward 'said air inlet chamber or outwardly of said opening, .said mecha'nism normallypositioning said elongated elements for directing the said air issuingfr'om said air outlet chamber toward said air inlet chamber, said mechanism positioning saidfilongated ;elements for directing the said air issuing 'from said air outlet chamber outwardly of said 'opening whenevera wind capable of defiecting said air ,screen'impinges upon said airscreen, said mechanism responding to inwardideflections of said air screen to move said elongated elements' and' thereby provide air passages between saidelongated elements that incline outwardly of' said opening.

10. A device that can; direct air across an opening to ;formen air screen of substantial depth for filling a substantial portion of said opening and that, comprises an air inlet chamber at one side of said opening, an air outlet chamber at the 'opposite sideof said opening, an air passage extending from said air inlet chamber to said air outl et charnber, an air-moving element to draw air into said air inlet chambe' and to move said air through said air passage to said air outlet chamber and across said opening to said air inlet chamber, said air outlet chamber having a large exit adjacent said opening, and a plurality of closely adjacent, elongated elements that arespaced apart depthwise of said opening in the direction of traffic through said opening and that are adjacent said exit with then-leading edges confronting the interior of said air outlet chamber andwith their trailingedges confronting said opening, the elongatedside edges of said elongated elements defining a pluralityof elongated` passages for the air issuing from said exit of said air outlet chamber, said elongated elements being triangular in cross section with their apexes .as .the leading edges thereof and ,with their bases as the trailing ,edges thereof.

11. A device thatcan direct air across an opening to form an air screen .of substantial depth 'for filling a substantial portion of said opening and :that comprses an air inlet chamber fatone sidetof said opening, an outlet hamber at the opposite ,side of said opening, an air passage extendingfrom said air, inlet chamber to .said air outlet charnberan airmovingelement to draw air intosaid air inlet chamber and to move said air through said air-passage to.saidair outlet chamber .andacross said opening to, ,said ai rn1et, chamber, -said,.air outlet chamber having .alarge .exit adjacent .said opening, a plurality ,of clo sely djacent, elongated elements that arespaed apartdepthwieoflsaid opening in the direction of traflic through said openng and that &readjaeentsad exit, with their ,leadngcedgesconfrontingthe nteriorof said air outlet chamber and, with .theirtrailing edges confronting said op ning, the ,elongated side .edges of said elongated elements defininga plur'ali ty ofaelongated passages for the, air issuing from said extofsaid air, outlet chamber, said elongatedelements being .tri-

angular in cross section with their apexes as theleading edgestthereof and with their bases as the trailing edges form an air screen ofsubstantial depth for fillinga substantial portion of said opening and that comprises :an `air inlet chamber at one side of said openi an air outlet chamber at the opposite side of said opening an air passage extending from said air inlet chamber to` said air outlet chamber, an'air-moving element to` draw air into said airinlet chamber andtomove said air' through said air passage to said air outlet chamber' and across said opening to` said air inlet chamber, said. air :outlet chamber having an exit that is adjacent said opening and that extends depthwise of said opening in the direction of traffie through said opening to provide an air screen of substantial depth in the direction 'of trafiic through said opening, a motor that drives said air-moving element -to cause said air toenter said air inlet chamber and to pass through said air passage to said air outlet chamber-and to move across said opening to said air inlet chamber, a water spray for said' air inlet charnber that is adapted to remove foreign matter carriedgintosaid air inlet chamber by said air screen, a drain to remove the water supplied by said water spray, and a control device that varies the velocity of saidair issuing from said air `outlet chamber, said control device providing low velocty for the said air issuing from said air outlet chamber whenever there is no external wind impinging upon said air screen and providing higher velocity for the said air issuing-from said air outlet chamber and thereby stabilizing said air screen whenever a wind capable of deflecting said air screen impinges upon said air screen.

References Cited in the file of this patent UNITED STATES PATENT S 774,73o Van Kannel Nov 8, 1904 1,279,993 Cummings Sept. 24, 1918 2,62,578 Labus. Dec. 16, 1952 'FOREIGN PATENTS 307.257 .Switzerland- 1 May 13, 1955 

